FROM 5.4
Overwrite /JabberCam_v.swf
Overwrite /JabberCam.swf or /JabberCam_h.swf with JabberCam.swf
Overwrite (edit) /jabbercam/language/lang_en.ini and any other language you are using

FROM 5.3
Overwrite /JabberCam_v.swf

FROM 5.2
Overwrite /JabberCam_h.swf with JabberCam.swf

FROM 5.1
Overwrite /JabberCam_h.swf with JabberCam.swf

FROM 5.0
Overwrite /JabberCam_h.swf with JabberCam.swf
Overwrite (edit) /jabbercam/language/lang_en.ini and any other language you are using
Overwrite (edit before) /jabbercam/config.php

FROM 4.5 and 4.4

Upgrading a modified CRC version to RVC 5.0 is possible but not recommended due to multiple changes in the .mxml layout. Compare JabberCam.mxml with former JabberCam_h.mxml and JabberCam.as before upgrading.

FROM 4.4 (For testing purposes only, upgrade to 4.5 is not recommended!)
Overwrite /JabberCam_v.swf
Overwrite /JabberCam_h.swf
Overwrite (edit) /jabbercam/language/lang_en.ini and any other language you are using

FROM 4.3
Overwrite /JabberCam_v.swf
Overwrite /JabberCam_h.swf
Overwrite (edit) /jabbercam/language/lang_en.xml and any other language you are using

FROM 2.8
Overwrite ChatRouletteClone.swf
Edit and overwrite /jabbercam/config.php
Overwrite /jabbercam/functions.php
Overwrite and run /jabbercam/install.php
Overwrite (edit) /jabbercam/lang_en.xml and any other language you are using

Optional: Read the ENABLING Red5 IN CASE YOU HAVE YOUR OWN RED5 SERVER section

FROM PREVIOUS VERSIONS
When upgrading, you need to update at least ChatRouletteClone.swf and upload the jabbercam folder to your host.
Edit config.php and the lang_en.xml and other language files.
Change BgImage1.jpg, BgImage2.jpg and BgImage3.jpg (you have dozens of combinations, using language files)
Drop your existing database and import chatroulette_clone.sql
Run a cron job or access your_domain.com/jabbercam/functions.php?task=clean on a regular basis.